The pressure to appear flawless is all-consuming, for fans as well as acts — and South Korea’s booming plastic surgery industry feeds directly into this obsession.

Beauty is as important for the boys as for the girls. Pictured, Super Junior in Macau.Source:Getty Images

Author Roald Maliangkaij, who has just published the book K-pop — The International Rise of the Korean Music Industry, tells news.com.au: “The fashion, the hair, the clothes, the style — these things are not always attainable. Probably 95 per cent of performers have had surgery.

“It’s mainly the face: the jawline, noses, eyelids, lips ... It can be a significant difference.

“You do see fans copying, and there are cases where it goes wrong, causing disfigurement.”

Thousands visit Seoul each year for cosmetic surgery, mainly from around Asia, but increasingly from western countries like Australia, where K-pop has a major following.

The South Korean capital’s buses advertise interpretative services and accommodation for plastic surgery tourists in areas like Gangnam, the affluent neighbourhood made famous by Psy’s breakthrough hit.

“It’s marketing a dream,” says Dr Maliangkaij. “Although that’s not so different to US pop.”

While the typical K-pop fan is a Korean girl, aged 13-15 and interested in fashion, the net is widening.

Its addictive culture has male as well as older fans hooked, with large fanbases in China, Thailand, Japan, Malaysia, Indonesia and South America.

It isn’t just girls who are expected to look perfect, either.

“Boys are also marketed as eye-candy, and sexualised,” says Dr Maliangkaij. “There are reports that vast numbers of men are seeking cosmetic surgery in order to get better jobs.”

Idealistic fans expect their idols to be faultless.Source:Getty Images

This doesn’t mean there is no inequality between the genders. Women in Korea are paid less, and expected to focus on finding a husband rather than a career.

The country has a vast sex industry, and female K-pop stars have reportedly been forced to quit music after being sexually harassed.

While a band’s management will pile on the pressure to get the perfect look, the impossibly high ideals come from fans too.

Not only is physical appearance important, supporters expect their idols to behave like model citizens.

Stars have faced online witch-hunts after questions over their authenticity.Source:Getty Images

“All the main acts have charities they publicly support,” says Dr Maliangkaij. Fans trying to emulate their idols compete to donate the most time and money to charities, which may focus on anything from migrants to lost pets.

When stars fall short of fans’ intense expectations, they face retribution.

Supporters’ rage can be incited by band infighting, poor performances or even, in the case of the band Sistar, how much attention each member gets.

Tablo, an idol suspected of lying about having a degree, was hounded by vicious internet rumours until he proved it was true.

“People are saying, you can’t lie, you’re supposed to be perfect,” says Dr Maliangkaij. “Celebrities are bullied constantly on the internet, and it has led to suicides.”

Sistar came under scrutiny when supporters became upset at the lack of airtime given to one particular member.Source:Getty Images

The most obsessive fans are known as Sasaeng, or “private fans”.

They have been known to install hidden cameras in their idols’ homes and cars, write love letters in menstrual blood and poison rival groups’ drinks, Yahoo! Singapore reported.

They have attacked other fans who have got close to their idols, left urine and faeces in stars’ homes and even assaulted the objects of their affection for failing to give them the attention they crave.

Some Korean taxi firms now offer services where they will chase down idols for Sasaeng, speeding at up to 200km/h and causing accidents.

Tensions in TVXQ led to the appearance of splinter group JYJ, after fierce arguments through lawyers.Source:Getty Images

But Dr Maliangkaij says some are now tiring of K-pop’s painfully unrealistic image.

“There’s a bit of a backlash in Korea from older fans who are into ‘real music’, written by Koreans,” he says.

They want to hear bands create their own songs, instead of being fed cookie-cutter tracks by often Scandinavian writers, who have a reputation for catchy, kitschy tunes.

Fans and acts alike are bored of the monotony of identikit tracks and the strict control of the industry.

Idols are ditching their management to avoid being pawns — as was the case with JYJ, a splinter group formed in 2010 from TVXQ.

Yet there isn’t always an escape. TVXQ had their phone lines tapped, their apartments broken into by fans who wanted to kiss them in their sleep and one member was hospitalised after being given a drink with glue mixed in.

But JYJ have also faced physical harassment, and been watched by cameras hidden in car parks.